Clinical Evaluation of Calcium Metabolism in Adult T-Cell Leukemia/Lymphoma

Mechanism of hypercalcemia in adult T-cell leukemia: overexpression of receptor activator of nuclear factor κB ligand on adult T-cell leukemia cells

“…10,12,13 Several cytokines, such as interleukin-1 (IL-1), 14 transforming growth factor ␤, 15 and parathyroid hormone-related protein (PTH-rP) 16 have been implicated in ATL-associated hypercalcemia. Among these factors, PTH-rP is considered to play an important role by stimulating OCLs, resulting in increased bone resorption.…”

Adult T-cell Leukemia with Hypercalcemia-induced Metastatic Calcification in the Lungs Due to Production of Parathyroid Hormone-related Protein.

“…The present case involved ATLwith severe hypercalcemia, complicated by respiratory insufficiency due to metastatic calcification in the lungs. Hypercalcemia has been reported to be a commoncomplication ofATL, with an incidence of40% to 70% (10)(11)(12)(13)(14)(15)20). At autopsy, proliferation of osteoclasts with extensive bone resorption has been observed in cases with ATL(21).…”

“…At autopsy, proliferation of osteoclasts with extensive bone resorption has been observed in cases with ATL(21). This hypercalcemia was closely associated with elevated nephrogenous cyclic adenosine monophosphate and reduced serum 1, 25-dihydroxyvitamin D3 concentration with a low to normal immunoreactive PTH level (20). The humoral factor, PTHrP produced by tumor cells in ATL, is believed to play an important role in the development of hypercalcemia by stimulating osteoclastic bone resorption (9,15,18,(22)(23)(24)(25).…”

Adult T Cell Leukemia/Lymphoma

“…56 Patients present with typical symptoms of hypercalcemia, such as lethargy, constipation, confusion, dehydration, and polyuria.37 54-5' The hypercalcemia may be unresponsive to treatment with standard measures until chemotherapy for ATLL is instituted. Not infrequently, hypercalcemia is associated with the terminal phase of the disease and may be a cause ofearly death.…”